The story begins with a sheet of paper. According to expelled Trinamool Congress MLA Sabyasachi Dutta, he and a number of colleagues put their names on what they understood to be a routine attendance register. They did not, he insists, sign any resolution. What that paper allegedly became — a formal letter nominating veteran TMC figure Sobhandeb Chattopadhyay as Leader of Opposition in the West Bengal legislative assembly — is now the subject of a criminal forgery investigation by the state Criminal Investigation Department.

The distinction matters enormously. The West Bengal assembly's Leader of Opposition post is not a ceremonial footnote. It is the official face of legislative resistance inside the house, with formal recognition, resources, and political weight. That TMC now occupies this role — in its own state, having lost the 2021 assembly majority narrative and found itself in opposition in Delhi's calculus if not Kolkata's — makes the nomination letter a document of real consequence. If signatures were harvested under false pretenses to manufacture consent for that nomination, that is not an internal party squabble. That is, legally, a forgery.

The CID has now recorded statements from at least thirteen sitting TMC MLAs in connection with the alleged fraud. Abhishek Banerjee — the party's national general secretary and Mamata Banerjee's nephew, widely regarded as the organization's second power center — has been summoned for questioning. That the investigative arm of a state government run by the very party under scrutiny is pursuing this case with apparent seriousness either reflects genuine institutional independence or a more complicated internal factional calculation. Possibly both.

Into this charged atmosphere steps the expelled MLA bloc. Two legislators have now been formally expelled from the party, officially for anti-party activities. The timing is not coincidental. Their public backing of a challenge to the party leadership — and their willingness to cooperate with, or at minimum not resist, the CID inquiry — positions them as the visible edge of a faction that may run deeper than two names on an expulsion order. Several other MLAs have been conspicuously absent from party events or slow to affirm loyalty, a pattern that veteran Bengal political observers recognize as the opening choreography of a potential split.

The comparison being drawn in political circles is to the Shiv Sena rupture in Maharashtra, where a legislative bloc defected, claimed the party's organizational legitimacy, and eventually wrested even the party's official symbol from its founder's family through the Election Commission. That process was messy, protracted, and ultimately devastating for the Uddhav Thackeray wing. Whether TMC is structurally vulnerable to the same mechanism is a genuine question — one that Mamata Banerjee's loyalists are working urgently to answer in the negative, and that her critics are working equally hard to keep open.

Mamata herself has not retreated into defensive silence. She has announced and proceeded with a public sit-in protest in Kolkata — notably without police permission — a move that serves dual purposes. It reasserts her as a street-level fighter, the identity that built TMC in the first place, and it frames her opponents as aligned with an establishment that denies democratic space. Whether that framing lands depends heavily on whether the signature forgery case produces evidence that implicates the party apparatus around her, or whether it fizzles into procedural inconclusion.

The Suvendu Adhikari dimension adds further texture. Adhikari — once a TMC heavyweight, now the Leader of Opposition from the BJP side and the man who defeated Mamata in Nandigram in 2021 — has watched this unfolding with undisguised interest. His trajectory from TMC insider to its most effective external antagonist is exactly the template that worried Mamata's inner circle is trying to prevent from being replicated. The fear is not merely that a few MLAs go independent. The fear is that they go somewhere organized and well-funded.

What is confirmed: the CID is conducting an active investigation, multiple MLAs have given statements, two have been expelled, and Abhishek Banerjee has been summoned. What is alleged: that signatures were deliberately misrepresented on a formal nomination document. What remains unknown: whether the probe will produce prosecutable evidence, whether the dissident bloc has the numbers and the nerve to force a formal split, and whether the Election Commission would entertain a rival claim to the TMC name and symbol if that moment ever came. Bengal politics has always been played at high intensity. Right now it is playing for existential stakes.